ABSTRACT
In many civil engineering applications, such as pavements, bridge deck overlays, and offshore structures, the flexural fatigue strength and endurance limit are important design parameters, because these structures are designed on the basis of fatigue loadings. This chapter summarizes the state of knowledge of fiber reinforced concrete (FRC) behavior under cyclic loads, its fatigue strength and endurance limit and includes a state of the art of methods to model that behavior. This survey is limited to the most commonly used FRC. It includes a comparative evaluation of fatigue properties of concrete with four types of fibers (hooked-end steel, straight steel, corrugated steel, and polypropylene) and two different volume percentages (0.5 and 1%). The addition of the fibers causes a considerable increase in flexural fatigue strength and the endurance limit for 4 million load cycles. Hooked-end steel fibers cause the most improvement (143%), while straight steel and polypropylene fibers have the least effect. Data on the flexural fatigue strength of SIFCON are presented, as well as data on FRC under flexural and compressive cyclic load. Statistical and probabilistic concepts are introduced for generating S-N curves and predicting the fatigue life of FRC beams. A summary of mechanical models is given for numerically simulating the fatigue behavior of FRC.
